Method of making universal joint bodies



July 24, 1956 e. E. DUNN ETAL METHOD OF MAKING UNIVERSAL JOINT BODIES 5Sheets-Sheet 1 Original Filed Sept. 25, 1952 a 4m? VIII 4 H Ill my w 1fi Z 5 NW w, 2 lh 1| 5 1 2 a i l l 0 July 24, 1956 G. E. DUNN ET ALMETHOD OF MAKING UNIVERSAL JOINT BODIES Original Filed Sept. 25, 1952w/ll/V/lfl/ 5 Sheets-Sheet 2 INVENTORS. eZTflz/n July 24, 1956 e. E.DUNN ET AL METHOD OF MAKING UNIVERSAL JOINT BODIES 5 Sheets-Sheet 5Original Filed Sept. 25, 1952 w I II.. g V

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July 24, 1956 e. E. DUNN ETAL 2,755,543

METHOD OF MAKING UNIVERSAL JOINT BODIES Original Filed Sept. 25, 1952 5Sheets-Sheet 4 IIIII -l- July 24, 1956 G. E. DUNN ET AL METHOD OF MAKINGUNIVERSAL JOINT BODIES 5 Sheets-Sheet 5 Original Filed Sept. 25, 1952INVENTORS. Z fla If F77) EX ll/IETHOD OF MAKING UNIVERSAL JOE IT BODIESGeorge E. Dunn, Dearhorn, and Alan T. McHenry, Grosse Pointe, MiclL,assignors, by; mesne assignments, to Chrysler Corporation, Detroit,Mich., a corporation of Delaware Original application September 25,1952, Serial --No. 311,504. Divided and this application July 24, 1953,Serial No. 377,582

Claims. (Cl. 29-535) guides with a center bore parallel to and betweenand intersecting the guides, the guides being openatone end of the bodyand closed at the other end thereof. The body is-provided with aradially extending, continuous attaching flange at the open end of theguides and with -a neck at the other end defining a continuationof'the'center bore.

It has been the practice heretofore to make these bodies in either oftwo ways. According to one method, a blank of sheet stock is subjectedto a series of drawing opera tions to form a stamped body, and whilethis'method has in general proved satisfactory heretofore, such stampedbodies will yield under high torque'loads at'the intersections betweenthe guides and the'center bor'e. This'tendency of such stamped bodies toyield at such intersections causes the joint body to open up, therebyincreasing the clearances between the balls and guides, which results indeterioration and premature failure of the joint. This tendency ofstamped bodies to open up at such intersections is due to the fact thatsuch intersections are a critical part of the body and joint bodies ofthis type meow being used at working loads which border closely upon thecapacity of the joint body. As it is not feasible "for competitive andperformance reasons to increase thesiz'e of'the joint body, the recentadvent of cars with greatly increased horsepower and torque hasseriously 'afie'cted further use of joints of this type using'stampedbo'dieg'in spite of the many inherent advantages of this type of joint.

Bodies of this type have heretofore also been made from forgings whereinthe center bore and guides have been bored out, but the cost ofmachining requiredby this method of producing bodies has been such asrepreclude its employment on joints made for original equipmentpurposes, as distinguished from joints made for sale tothe repair trade.

According to this invention, a joint bodyoftliis'ty'pe is made by aseries of forging operations which are employed to extrude a headedsolid metal body so as to form a rough joint body suitable for finishmachining operations, the finish machine operations requiredbingsubstantially the same as those required for a stamped body asheretofore made. This method has a number of advantages. In the firstplace, a forged body ofagiven size made according to the invention maybe subjected to a maximum working load of about 18,000 in. lbs., whereasa body of the same size made according tothe aforesaid stamping processmay be employed, say, for working loads up to only about 10,000 in. lbs.Thus, this invention makes it possible to approximately double'thecapacity of the joint body without increasing the size.

in addition, 'a forged body made according to'this invention employsless metal of a less expensive character Patent scrap losses.

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thanthat required for stamped bodies. For example, 'for a given size,aslug of metal stock required for a body 'made according to thisinvention is approximately 2 1b., 4 oz. "and the finished 'b'ody weighsapproximately '1 1b., 10 /2 02., whereas the same size bodymade-according'to the conventional stamping niethodrequires a blank of lapproximately 3 lb. *and the resulting finished body weighs'approximately llb. '8 oz. Thus,"according to this inventionsubstantially less metal of a less expensive type "is re'quired, therebysubstantially reducing material costs and The scrap fror'nf-thepreviously described forging'and machining 'method now rgenerally'usedisconsiderable, since the center bore and the guides must all be boredout, and thefmtal so removed is an scrap.

'In addition to "the 'incr'easesin strength due to theme of'a forgedbody, *the method herein disclosed makes it possible to strengthen Ttliebody at various critical places, as will be hereinafter :pointed'out inmore detail.

A principal object of the invention, therefore, is to provide a new andimproved body for universal joints of-the type referred to.

Another objecnofthe inventionis toiproduce a new and improved method ofmaking joint "bodies'of the type referred-to.

Gther and furtherobjects of the invention will be apparent from thefollowing descriptionand claims and may beunderstoodby'referenceto theac'compa'nying drawings, of which there'arefive'sheets, which by wayof'illustration show a preferredenibodiment of the invention and what wenow 'consider'tobe the best mode in 'which we have contemplated applyingthep'rinci'ples or our invention. Other :embodiinentsof the inventidnmay be used with'0ut"departing from the scope of'the present inventionas set forth inthe appended claims.

In the drawings:

Fig. l is aperspective view'of aslugofmetal stock useful for makingjoint-bodies"according to tlie r'nethod herein disclosed.

Fig. 2 is a fragmentary sectional viewthr'ough aforging-die;asse'rnblyand'showing the 'iirst step ofthe'metln odhereindisclos'ed. -Inthis and in'other figures the shape of the m'etalbody which isbeingforme'd is shown in dot and dash lines beforethejoperation"in'question.

Fig. 3 is a plan viewdfFi-gJZ 'with'the'punch removed.

Fig. 4'is-a sectionalview similart'o Fig. 2 but taken 'at right anglesthereto.

Figs. 5, Sand 7--illusttatethe-nextstep in the method, Fig. 5 being aplan-view of the'partially formedbody and the cavity die, Fig. 6 being avertical sectional view through the same and with the-punch die at thebottom of its stroke, and Fig.7 being-another vertical-sectional'view atright angles to Figi6.

Figs. 8, 9 and 10-illustratethe next'step in the method, Fig. 8 being aplan view of the :partially formed-body and the cavity die, Fig. '9-b'eing a vertical sectional view through the same with the-punch die atthe bottom of its stroke, and Fig. 10 beinganother vertical sectionalview at right angles to Fig. 9.

Fig. 11 is a vertical sectionalview illustrating the step of piercingthe neck of the joint body.

Fig. 12 is a verticalsectional view through the forging dies and ajointbody, andillustrating the 'step'of bell mouthing-the neck to'itsfinal form 'a'nd the accompanying extrusion of-metal 'to'form anexternal stiffening rib transversely of the body adjacent the closed'endof the guides. M

Fig. 13'is a perspective view of -a-finished joint body.

Figs. 14 and 15 are sectional views thereof, taken in planes along thelines 14-' 1'4 an'd 15'-1"5 of'Fig.

Fig. 16 is a transverse sectionalview takenin a plane along the line16'-'-16of"Fig. 15.

As illustrated in Figs. 13, 14, 15 and 16, a universal joint bodyembodying the invention consists of a hollow, metal, one-piece bodyhaving opposed and parallel cylindrical guides 22 with a center bore 24parallel to and between and intersecting such guides. The guides 22,sometimes called raceways, are open at one end of the body and closed atthe other end thereof. A radially extending, continuous attaching flange26 is formed at the open end of the guides, the flange being providedwith bolt holes 28 to permit the assembly of the body to the companionflange with which it is used. The center bore 24 is open at both ends. Abell mouthed neck 30 defines a continuation of the bore and projectsbeyond the closed end of the guides and is provided with an annulargroove 32 forming a seat for the sealing boot of the joint. Between theflange 26 and the neck 30 the body is substantially oval shaped intransverse section normal to the bore and guides.

The Wall thickness of the body is substantially uniform from the open tothe closed end of the guides and around the body normal to the guides,except adjacent the intersections 34 of the guides 22 and the centerbore 24, and at such intersections the wall thickness is substantiallygreater so as to reinforce the body along the lines of theintersections. The body is also formed to have an integral externalstiffening rib 36 which extends transversely around the body adjacentthe closed end of the guides. This rib 36, together with the thickerwall sections at the intersections 34, strengthens and stifiens the bodyso as to reduce the tendency of the raceways to open up at theintersections between the guides 22 and the center bore 24. The body isalso formed to have diametrically opposed stiffening ribs 38 whichextend between the flange 26 and the external portions of the centerbore 24.

The guides or raceways 22 are finished by machine operations since theyform bearing surfaces for the balls and centering buttons, and theguides 22 and the center bore 24 are also case hardened. The face 40 ofthe flange 26 is provided with a finished surface in a plane normal tothe axes of the guides 22 and center bore 24,

and in addition the outer rim 42 of the flange is provided with afinished surface concentric with the axis of the center body 24 foraccurate nesting of the body in the companion flange.

The preferred method for making such bodies is as follows. A slug of lowcarbonl0/20hot rolled steel bar stock of the shape shown in Fig. l isheated to a temperature of the order of 2250" to 2300 F., and such slugpreferably is preformed so as to have the shape of the body 52 as shownin dot dash lines in Figs. 2, 3 and 4. The preforming operation shortensand bulges the body 50 to produce a body having the shape as indicatedat 52, and this operation cracks: and removes the scale created duringthe heating aforesaid. It will also be noted that the preformingoperation partially forms one end of the slug 52 as shown in Fig. 2 soas to get a preliminary distribution of the metal.

The slug 52 is then inserted in the cavity 54 of the cavity die 56, asshown in Figs. 2, 3 and 4. The punch die 58 is then driven into the body52 along the axis thereof as shown in Figs. 2 and 4, thereby extrudingthe slug 52 into the hollow shape 60 as shown in Figs. 2, 3 and 4, thedies 56 and 58 cooperating to roughly but approximately form the insideand outside shape of the body except for the neck and the flange.However, this operation accumulates a mass of metal 62 which willsubsequently be used to form the neck 30, and a mass of metal 64 aroundthe open end of the body which will subsequently be used to form theflange 26. The foregoing and the following forging operations are allcarried on in rapid succession while the body is in its highly heatedcondition. The inner'solid line 66 shown in Fig. 3 shows the insidecontour of the hollow body 52, the punch die 58 having been removed. Thepin 68 is a knockout pin for the die 56.

In the next step, as shown in Figs. 5, 6 and 7, the body 60 as formed inthe preceding operation is illustrated in dot dash lines, while theshape of the body 70 after the operations illustrated in Figs. 5, 6 and7 is shown in solid line and is cross hatched. In the operations shownin Figs. 5, 6 and 7 the cavity die 72 cooperates with the punch die 74to bell mouth the open end of the body 70 as indicated at 76 and tosquare the bottom or closed ends of the guides as indicated at 78. Theneck is also partially extruded as shown at 80. The dies 72 and 74 areslightly larger in cross section than the dies 56 and 58. This expeditesthe insertion of the body 60 into the cavity of the die 72 and alsoresults in a slight expansion of the size of the body toward its finalshape and size.

In the next operation, as shown in Figs. 8, 9 and 10, the partly formedbody 70, shown in dot dash lines, is inserted in the cavity of thecavity die 82, and the cavity die 82 cooperates with the punch die 84when driven into the body 70 to form the flange 26 and to finish theextrusion of the neck 30 and to bring the outside of the body to itsfinal size and the inside of the body to size for machining. Thestiffening ribs 38 are also formed in this step.

After the operation shown in Figs. 8, 9 and 10, the body, now indicatedat 86, is inserted in a die (not shown) to trim the flash 88 from theflange 26, and the body 86 is then inserted in a cavity die 90, as shownin Fig. 11. A piercing die 92 is then employed to pierce the neck 30 soas to remove therefrom the transverse section of metal which was leftafter the operations disclosed in Figs. 8, 9 and 10. Thereafter, thebody is assembled in the die means as shown in Fig. 12. In thisoperation the bottom 78 of the raceways or guides 22 rests upon theupper surface of a pair of pivoted die members 94 pivotally supported at96 on the cross piece 98 which is bolted to the plate 100. A pair ofreciprocable dies 102 is then moved together so as to close around andengage the outer surface of the body 86 as shown, it being observed thatthe dies 102 are provided with relief grooves 104 which extend all theway around the body 86 at the closed ends of the guides. The dies 102are provided with portions 106 which cooperate with the punch die 108 tobell mouth the neck 30 to its final form, the punch die 108 upon beingdriven into the neck 30 expanding the same to its final form and alsoengaging and expanding the pivoted die members 94 so as to extrude metalinto the relief grooves 104 to form the rib 36. The die members 94support the body 86 during this operation and maintain the shape of theinner surface of the guides 22 and force the metal displaced by thepenetration of the die member 108 into the neck into the groove 104. Itis understood that the die members 102 come together at their sideedges, the die members 102 forming in effect a split die so as to permitremoval of the body 86 after the formation of the rib 36 and the neck30.

While we have illustrated a series of steps with certain formingoperations being carried on in each step, we contemplate that the numberof steps might be reduced by combining certain of the operations so thata lesser number of operations would be required to form the slug 50 intoa body of the desired shape. After removal from the dies, as shown inFig. 12, the body is ready for the machining operations, and since theseoperations are the same as those employed for machining stamped bodies,there is no necessity of setting forth the same here.

It should be pointed out that the method herein disclosed makes itpossible to provide thicker wall sections along the intersections 34,whereas in the method employed for producing stamped bodies the contourof the outer wall follows that of the inner wall, with the result thatin stamped bodies the intersections between the guides and the centerbores are a critical part of the joint body.

It should also be noted, as shown in Figs. 14 and 15, that the wallthickness of the body is substantially uniform from one end to theother, whereas with stamped bodies the wall thickness tapers with thedepth of the draw. For example, in a stamped joint body of a given size,the wall thickness at the open end of the guides is 7& in., whereas atthe closed end of the guides it is tapered down to A in. This cannot beavoided in drawing operations. According to the method herein disclosed,not only are the wall thicknesses substantially uniform from one end ofthe guides to the other, but also the method herein disclosed makes itpossible to form the stiffening rib 36 around the body at the closed endof the guides which cooperates with the thickened sections along theintersections 34 to greatly increase the capacity of the body, aspreviously indicated.

While we have illustrated and described a preferred embodiment of ourinvention, it is understood that this is capable of modification and wetherefore do not wish to be limited to the precise details set forth butdesire to avail ourselves of such changes and alterations as fall withinthe purview of the following claims.

We claim:

1. The method of forming a hollow, metal, universal joint body havingopposed and parallel cylindrical guides with a center bore parallel toand between and intersecting said guides, a radially outwardly extendingattaching flange at one end and an axially extending neck at the otherend, which comprises positioning a heated solid metal body consisting ofa slug of steel bar stock in die means which will determine the outsideshape of said body, forcing a series of die punches into said body alongthe axis thereof while so positioned so as to extrude the metal of thebody between said punch and die means thereby to roughly butapproximately form said guides and center bore and accumulate metalstock around the open end of said body for said flange and metal stockat the other end of said body to form said neck; to square the closedend of said guides; to form said radially extending attaching flange; tobring the outside of the body to its finished size and the insidethereof to size for finish machining operations and to form a neck onone end of said body; trimming said flange to size and piercing saidneck so as to remove metal therefrom which extends transversely thereof;forcing a die into said neck so as to bring the same to its finishedsize and to cause the metal of said body in the plane transversely ofsaid guides at the closed end thereof to flow so as to form an externalstiffening rib which extends transversely of the body adjacent theclosed end of the guides.

2. The method of forming a hollow, metal, universal joint body havingopposed and parallel cylindrical guides with a center bore parallel toand between and intersecting said guides, a radially outwardly extendingattaching flange at one end and a bell mouthed axially extending neck atthe other end, which comprises positioning a heated solid metal bodyconsisting of a slug of steel bar stock in die means which willdetermine the outside shape of said body, forcing a series of diepunches into said body along the axis thereof while so positioned so asto extrude the metal of the body between said punch and die meansthereby to roughly but approximately form said guides and center boreand accumulate metal stock around the open end of said body for a flangeand metal stock at the other end of said body to form a neck; to squarethe closed end of said guides; to form a flange; to bring the outside ofthe body to its finished size and the inside thereof to size for finishmachining operations and to form a neck on one end of said body; andtrimming said flange to size and piercing said neck so as to removemetal therefrom which extends transversely thereo,

3. The method of forming a hollow, metal, universal joint body havingopposed and parallel cylindrical guides open at one end with a centerbore parallel to and between and intersecting said guides, an attachingflange at the open end of said guides and an axially extending neck atthe other end defining a continuation of said bore, which comprisessubjecting a heated solid metal body consisting of a slug of a steel barstock to a series of extrusion operations by and between a series ofmale and female dies so as to extrude the metal of said body to formmetal walls of substantially uniform thickness defining the inside andoutside shape of said guides and center bore, and relatively thick metalwalls at the intersections of said bore and guides, a radially extendingattaching flange at one end of said guides, and a neck defining acontinuation of said bore and projecting beyond the other end of saidguides.

4. That method according to claim 3 which includes the step of expandingthe interior of said body transversely of the closed end of said guidesto form an integral external stiffening rib around said body.

5. The method of forming a hollow, metal, universal joint body havingopposed and parallel cylindrical guides with a center bore parallel toand between and intersecting said guides, an attaching flange at one endand a bell mouthed neck at the other end defining a continuation of saidbore, which comprises subjecting a heated solid metal body consisting ofa slug of steel bar stock to a series of extrusion operations by andbetween a series of male and female dies so as to extrude the metal ofsaid body to form metal walls defining the inside and outside shape ofsaid guides and center bore, a radially extending attaching flange atone end of said guides, and a neck defining a continuation of said boreand projecting beyond the other end of said guides.

References Cited in the file of this patent UNITED STATES PATENTS1,024,840 Erhardt Apr, 30, 1912 1,824,810 Ford Sept. 29, 1931 1,877,342Malby Sept. 13, 1932 1,881,877 Nickelsen Oct. 11, 1932 2,028,996 SautierJan. 28, 1936 2,321,085 Hubbard June 8, 1943 2,344,803 Criley Mar. 21,1944 2,371,716 Snell Mar. 20, 1945

1. THE METHOD OF FORMING A HOLLOW, METAL, UNIVERSAL JOINT BODY HAVINGOPPOSED AND PARALLEL CYLINDRICAL GUIDES WITH A CENTER BORE PARALLEL TOAND BETWEEN AND INTERSECTING SAID GUIDES, A RADIALLY OUTWARDLY EXTENDINGATTACHING FLANGE AT ONE END AND AN AXIALLY EXTENDING NECK AT THE OTHEREND, WHICH COMPRISES POSITIONING A HEATED SOLID METAL BODY CONSISTING OFA SLUG OF STEEL BAR STOCK IN DIE MEANS WHICH WILL DETERMINE THE OUTSIDESHAPE OF SAID BODY, FORCING A SERIES OF DIE PUNCHES INTO SAID BODY ALONGTHE AXIS THEREOF WHILE SO POSITIONED SO AS TO EXTRUDE THE METAL OF THEBODY BETWEEN SAID PUNCH AND DIE MEANS THEREBY TO ROUGHLY BUTAPPPROXIMATELY FORM SAID GUIDES AND CENTER BORE AND ACCUMULATE METALSTOCK AROUND THE OPEN END OF SAID BODY FOR SAID FLANGE AND METAL STOCKAT THE OTHER END OF SAID BODY TO FORM SAID NECK; TO SQUARE THE CLOSEDEND OF SAID GUIDES; TO FORM SAID RADIALLY EXTENDING ATTACHING FLANGE; TOBRING THE OUTSIDE OF THE BODY TO ITS FINISHED SIZE AND THE INSIDE THEROFTO SIZE FOR FINISH MACHINING OPERATIONS AND TO FORM A NECK ON ONE END OFSAID BODY; TRIMMING SAID FLANGE TO SIZE AND PIERCING SAID NECK SO AS TOREMOVE METAL THEREFROM WHICH EXTENDS TRANSVERSELY THEREOF; FORCING A DIEINTO SAID NECK SO AS TO BRING THE SAME TO ITS FINISHED SIZE AND TO CAUSETHE METAL OF SAID BODY IN THE PLANE TRANSVERSELY OF SAID GUIDES AT THECLOSED END THEREOF TO FLOW SO AS TO FORM AN EXTERNAL STIFFENING RIBWHICH EXTENDS TRANSVERSELY OF THE BODY ADJACENT THE CLOSED END OF THEGUIDES.